Hierarchical inter-layer prediction in multi-loop scalable video coding

Abstract

In examples, a method comprises receiving, by a decoder, a scalable bitstream including a plurality of layers of bitstreams The method comprises determining, by the decoder, a target layer of the plurality of layers of bitstreams to be decoded. The method also comprises demultiplexing, by the decoder, the plurality of layers of bitstreams from the scalable bitstream. The method further includes decoding, by the decoder, each of the plurality of layers of bitstreams that is at or below the target layer and associated with the target layer. The method also comprises outputting, by the decoder, a video based on each of the plurality of layers of bitstreams that is at or below the target layer and associated with the target layer.

What is claimed is: 
     
       1. A method comprising:
 receiving, by a decoder, a scalable bitstream including a plurality of layers of bitstreams; 
 determining, by the decoder, a target layer of the plurality of layers of bitstreams to be decoded; 
 demultiplexing, by the decoder, the plurality of layers of bitstreams from the scalable bitstream; 
 decoding, by the decoder, each of the plurality of layers of bitstreams that is at or below the target layer and associated with the target layer; and 
 outputting, by the decoder, a video based on each of the plurality of layers of bitstreams that is at or below the target layer and associated with the target layer. 
 
     
     
       2. The method of  claim 1 , further comprising:
 decoding, by the decoder, a respective highest level value from the scalable bitstream for each of the plurality of layers of bitstreams, wherein the respective highest level value corresponds to a highest level used for inter-layer prediction by each of the plurality of layers of bitstreams. 
 
     
     
       3. The method of  claim 2 , wherein:
 the highest level value is a highest temporal level. 
 
     
     
       4. The method of  claim 2 , wherein:
 decoding, by the decoder, each of the plurality of layers of bitstreams that is below the target layer and associated with the target layer includes decoding pictures that are in levels at or below the respective highest level value for each layer. 
 
     
     
       5. The method of  claim 1 , further comprising:
 decoding, by the decoder, a maximum decoded picture buffer (DPB) size from the scalable bitstream, the maximum DPB size indicating a memory size of the decoder needed for decoding each layer of the plurality of layers of bitstreams that is at or below the target layer and associated with the target layer. 
 
     
     
       6. The method of  claim 5 , further comprising:
 in response to determining that DPB size is greater than an available memory space of the decoder, decoding, by the decoder, a second target layer. 
 
     
     
       7. The method of  claim 5 , further comprising:
 in response to determining that DPB size is greater than an available memory space of the decoder, transmitting, by the decoder, an error signal. 
 
     
     
       8. The method of  claim 1 , wherein:
 the decoder includes a respective sub-decoder associated with each of the plurality of layers of bitstreams. 
 
     
     
       9. The method of  claim 1 , wherein:
 the plurality of layers of bitstreams includes:
 a base layer; 
 an intermediate layer; and 
 a top layer. 
 
 
     
     
       10. The method of  claim 9 , wherein:
 the decoder includes:
 a first up-sampler coupled between the base layer and the intermediate layer; and 
 a second up-sampler coupled between the intermediate layer and the top layer. 
 
 
     
     
       11. A computer program embodied on a non-transitory computer-readable medium, the computer program configured to cause a processor to:
 receive a scalable bitstream including a plurality of layers of bitstreams; 
 determine a target layer of the plurality of layers of bitstreams to be decoded; 
 demultiplex the plurality of layers of bitstreams from the scalable bitstream; 
 decode each of the plurality of layers of bitstreams that is at or below the target layer and associated with the target layer; and 
 output a video based on each of the plurality of layers of bitstreams that is at or below the target layer and associated with the target layer. 
 
     
     
       12. The computer program of  claim 11 , further configured to cause the processor to:
 decode a respective highest level value from the scalable bitstream for each of the plurality of layers of bitstreams, wherein the respective highest level value corresponds to a highest level used for inter-layer prediction by each of the plurality of layers of bitstreams. 
 
     
     
       13. The computer program of  claim 12 , wherein:
 the highest level value is a highest temporal level. 
 
     
     
       14. The computer program of  claim 12 , wherein:
 decode each of the plurality of layers of bitstreams that is below the target layer and associated with the target layer includes decoding pictures that are in levels at or below the respective highest level value for each layer. 
 
     
     
       15. The computer program of  claim 11 , further configured to cause the processor to:
 decode a maximum decoded picture buffer (DPB) size from the scalable bitstream, the maximum DPB size indicating a memory size needed for decoding each of the plurality of layers of bitstreams that is at or below the target layer and associated with the target layer. 
 
     
     
       16. The computer program of  claim 15 , further configured to cause the processor to:
 in response to determining that DPB size is greater than an available memory space, decode a second target layer. 
 
     
     
       17. The computer program of  claim 15 , further configured to cause the processor to:
 in response to determining that DPB size is greater than an available memory space, transmit an error signal. 
 
     
     
       18. The computer program of  claim 11 , further configured to cause the processor to:
 separately decode each of the plurality of layers of bitstreams. 
 
     
     
       19. The computer program of  claim 11 , wherein:
 the plurality of layers of bitstreams includes:
 a base layer; 
 an intermediate layer; and 
 a top layer. 
 
 
     
     
       20. The computer program of  claim 19 , further configured to cause the processor to:
 perform a first up-sampling between the base layer and the intermediate layer; and 
 perform a second up-sampling between the intermediate layer and the top layer.